1. Field of the Invention
This invention relates to a molded case circuit breaker, and more particularly, it pertains to a circuit breaker having a terminal shield for preventing electrical breakdown due to ionized gases exhausting from an arc chute chamber.
2. Description of the Prior Art
The control of exhausting gases from a circuit breaker during opening of the contacts has always been a problem. This is particularly true for circuit breakers of small physical size with high interrupting ratings. But where wiring terminals are used in close proximity to the circuit breaker vents, the problem is especially acute. When an arc occurs during opening of the contacts, ionized arc gases can cause a breakdown between the terminals of the circuit breaker and any metallic enclosure within which the circuit breaker is mounted. A breakdown of this type can develop into a ground fault and, if severe enough, create a phase-to-phase fault outside of the breaker.